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Updated: Aug 9, 2026
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A Simple, Rapid, and Quantitative Assay to Measure Repair of DNA-protein Crosslinks on Plasmids Transfected into Mammalian Cells
Published on: March 5, 2018
ADPRT-mediated decrease of cellular NAD content and the detection of chemically induced DNA damage--development of a
Proceedings of the Chinese Academy of Medical Sciences and the Peking Union Medical College = Chung-Kuo I Hsueh K'O Hsueh Yuan, Chung-Kuo Hsieh Ho I K'O Ta Hsueh Hsueh Pao
|January 1, 1990
Summary
This study reveals that DNA-damaging agents decrease cellular NAD content by stimulating ADP-ribosyl transferase (ADPRT) activity. Measuring this NAD reduction offers a simple, specific method for detecting DNA-damaging mutagens.
Area of Science:
- Biochemistry
- Molecular Biology
- Toxicology
Background:
- DNA-damaging agents like MNNG, MMS, and 4NQO stimulate ADP-ribosyl transferase (ADPRT) activity.
- This stimulation leads to a dose-dependent reduction in cellular NAD content following DNA damage.
Purpose of the Study:
- To explore a simple and specific method for detecting DNA-damaging mutagens.
- To investigate the measurement of ADPRT-mediated decrease in cellular NAD content as a detection strategy.
Main Methods:
- Utilized DNA-damaging agents (MNNG, MMS, 4NQO) and ADPRT inhibitors (3-aminobenzamide, nicotinamide).
- Employed beta-naphthoflavone, a mixed function oxygenase inducer, with human amnion FL cells.
- Assessed the induction of ADPRT-mediated NAD decrease by various chemical carcinogens/mutagens.
Main Results:
- DNA-damaging agents significantly reduced cellular NAD levels via ADPRT.
- ADPRT inhibitors partially or completely prevented NAD reduction caused by DNA damage.
- Specific carcinogens (aflatoxin B1, benzo(a)pyrene, etc.) induced ADPRT-mediated NAD decrease, while others did not.
Conclusions:
- A novel, cost-effective method for detecting DNA damage caused by chemical carcinogens/mutagens was developed.
- This method, based on ADPRT-mediated NAD depletion, shows specificity comparable to unscheduled DNA synthesis assays.
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